Does accepting OpenID logins protect me from spam?
OpenID Authentication merely allows you to validate that a user is allowed to use a given URL to log in. It doesn’t tell you anything about that user. This means that OpenID Authentication alone does not do anything to improve the spam situation, but since OpenID provides identity it is possible to build reputation and “human-checking” services on OpenID’s foundation. For example, you could use a CAPTCHA test in conjunction with an OpenID login to test if the remote user is a human. Once you have performed this test, you can store the fact that the CAPTCHA test succeeded to avoid testing that same user again in the future. OpenID also provides you with an authenticated handle to use for banning undesirable users or whitelisting trusted users. It is hoped that as OpenID support improves in blogging and forum software such facilities will become more readily available.
